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Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 1
ISSN: 2454-132X
Impact factor: 4.295 (Volume2, Issue6)
Available online at: www.Ijariit.com
DESIGN OF GATING SYSTEM FOR CONNECTING
HINGE BY TRADITIONAL AND SOFTWARE
METHOD
Ranjeet Mithari1, Mahesh Shinge
2, Pravin Rajigare
3
Department of Mechanical Engineering, Bharati Vidyapeeth’s College of Engineering, Kolhapur
1ranjeetmithari8888@gmail.com, 2msshinge@rediffmail.com,
3pravin.rajigare@gmail.com
________________________________________________________________________________
Abstract: There is various metal casting parameters which are now know through various experiment which are
quantified. These parameters should be controlled to improve quality of casted products. Metal casting involves
design, gating and risering system design, mold design, pouring of molten metal each process has its own effects on
quality of the casting. The flow of molten metal in mold accounts for almost 60% of the casting defects and due to this
fact it is quite obvious that it is important to pay more and adequate attention on preparation of molds in such a way
that molten metal will flow easily and fill the mould cavity properly. The molten metal is elastically deformable during
short interval of time when deformation causes stresses remain in the molten metal and hence in the cast parts. After
solidification these internal stresses remain in the metal. The change in temperature is the common cause of
volumetric changes in the molten metal. The paper will focus more on study of gating system design since flow of the
molten metal has significant effect due to this system. Design of this gating system reduces number of defects
produced in casting. This system results compare in between traditional and software. On the commercial front if we
look at prices trend charts of important foundry raw material we observe that there is consistent rise in prices and it is
quite obvious that these will go on increasing since we have no control over market circumstances and forces. In this
situation only alternative to remain competent and all foundries people to keep max control over all manufacturing
processes and hence related parameters so as to ensure the quality in the process itself.
Keywords—Casting, mold, gating system, inspection, defects.
I. Introduction
Casting is one of the many forming processes and it is one of the cheapest methods of giving finished shape. The liquid
metal is directly poured into a shaped mould t get the finished product. All other methods of shaping finished product
involved several steps. Thus for getting finished product by mechanical working, we must have first a cast ingot which is
given final shape by hot working or cold working. Machining involves chipping away from cast or worked material to
get the product shape. The element of a basic and very common gating system are the down spur through which metal
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 2
enters the runner and from which it in turn pass through the in gating into the mold cavity. That part of the gating system
which most restricts or regulates the rate of pouring is the primary chock. Gates and riser are often designed to take
advantage of the principle of controlled directional solidification which requires that freezing start fastest from the riser.
There are different types of Gates Parting gate, Bottom gate, Branch gate, Horn gate, etc.
II. Parameters system design of gating
Mold material, Fluid flow ,Sand, slag dross or other impurities, Rough surface, Entrapped gases ,Excessive oxidized
metal ,Localized shrinkage(pipe or macro shrinkage),Dispersed porosity or micro porosity, Incomplete fusion of liquid
metal where two streams meet (cold shut), Entrapped globules of pre solidified metal Metal penetration into sand mold
and/or core.
III. Methods and illustration of numerical calculation for gating and system
These numerical calculation methods are based on fluid mechanics and thermodynamics principles following examples
will give us clear idea about mathematical relations and calculations methods for the connect hinge.
A. Casting Data
Casting weight – 5.5 kg, Thickness – 6 mm , Height of casting – 180 mm ,Gross Weight – (5.5 × 4) + (R.R.Wt) = 28.6
B. Metal Data
Pouring temp – 14300C, Liquids temp – 13500C, Chemical Composition (SG Iron 600/10) - as below
C – (3.4 to 3.8) Si – (2.10 to 2.60) Mn – (0.3 max) S – (0.02 to 0.04) P – (0.03 to 0.06) Mg – (0.028 min)
Cu – (0.6 to 0.7), Density of liquid metal – (7000 kg/cm3) (C.I.) – (7.00 gm/cm3)
C. Data of mould
Height of metal in pouring basin – N.A, Height sprue (sleeve) – 125 mm , Height of casting in cope – 45 mm
D. Data of gating system
Gating system with filler Sprue: Runner: In gate 1.0: 1.1: 1.2
Gating system with filler Sprue: Runner: In gate 1.5: 3.0: 1
Calculations
1. Calculate the carbon fluidity (factor) equivalent.
CFE = C% + %Si/4 + %P/2, CFE = 3.4 + 2.50/4 + 0.013/2, CFE = 3.4 + 0.625 + 6.5×10-3, CFE = 4.0315
2. Calculate fluidity – P.T. = (Pouring temp.)
F = 14.9× (CFE) + 0.09 (P.T.) – 153.4, F = 14.9× (4.0) + (0.09) (1380) – 153.4, F = 30.4
3. Fluidity factor
K = F/40, K = 30.4/40, K = 0.76
4. Calculate pouring time
T = 1.483 (K) (0.95+0.046t) n√W
Where,
K = Fluidity factor
t = Thickness of casting
W = Gross wt.
N = 2 (For wt. up to 450 kg)
T = 1.483 (K) (0.95+0.046t) n√W
=1.483 (0.76) [(0.95 + 0.046 × 6)] 2√28.6
= 7.38 sec
= 8.00 sec =9.00 sec. (Standard pouring time)
If we considered pouring temp 13500C then pouring time would be 12 sec. i.e. for lower temperature of metal pouring
time increases.
5. Calculate effective sprue height (H) or Static (Hst):
Schematic sketch
h=a P.L.
Here, a = Height of casting in cope, c = Total height of casting, h = Height of sprue above parting line (P.L.)
Effective sprue height:-
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 3
General formula H = 2hc – ca2 / 2c
Here, a = 45mm, c = 180 mm, h = 150 mm
Case 1: For top gating Hst = Hsp
Case 2 : For bottom gating Hst = Hsp – c/2
Case 3 : For P/L gating Hst = Hsp – p2/2c
For this casting we have consider case 1
i.e. Hst = Hsp Hst = 150 mm
6. Choke area calculation:
Choke area Q = A×V
V/t = AC √2gH
A = W/ ℓct √2gH
Where, A = Choke area (m2), W = Gross wt. (kg), C = Friction factor (0.6 – 0.8), ℓ = Density of fluid (kg/m3)
g = Gravitational acceleration (m/s2), t = Pouring time (sec), H = Effective spure height (mtr.)
A = 28.6 / (7000)(0.6)(8) ×√2(9.81)(0.15)
= 4.9617× 10-4m2
= 4.9617 × 10-2 mm2
= 496.17 mm2
= 500 mm2
7. For pressurized gating system
As: Ar: Ag= 1: 2: 1
Where As = Area of spure, Ar = Area of Runner, Ag = Area of in gate
Here, As =
As = 4×A = 4×500 = 2000 mm2
Ar =2.0 As =2.0 ×2000 = 4000 mm2
Ag = 1.0 As = 1.0 × 2000 = 2000 mm2
Now we calculate actual dimensions from above area as –
Dimensions of sprue :160 mm , ᶲ 51
Diameter of sprue “D”
Area of sprue= π/4 × Ds2
DS2= 2000×4/ π
Ds = √2000 × 4/ π = 50.46 = 51 mm
Height of sprue = h
Area of sprue = Ds × hs
2000 = 51 × hs
hs = 40 mmhs = 4 × 40 = 160 mm
Dimensions of Runner plate 56 , ᶲ72
Diameter of Runner plate
Area of Runner plate = π/4×Dr2
Dr2= 4000×4/π
Dr = √4000 × 4/ π = 71.36 mm = 72 mm
Height of Runner plate = hr
Area of Runner plate = Dr × hr
4000 = 72 × hr
hr= 55.55 mm
hr= 56 mm
Dimensions of In gate
Ag = 2000 mm2 for one in gate area = Ag/4
Ag = 2000/4, Ag = 500 mm2
Width of in gate
Area of in gate = bg × hg
Suppose hg = 20 mm
Area of in gate = bg × hg
500 = bg × 20
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 4
bg= 500/20 = 25 mm
V. Inspection, Testing and Results
Visual inspection provides a means of detecting and examining a variety of surface flaws, such as corrosion,
contamination, surface finish, and surface discontinuities on joints. By doing the inspection following defects are occurs-
Shrinkage Defects, Cold Defects, Blow Hole, Mismatch Defect,
Fig.1 Shrinkage Defects in casting Fig.2 Blowhole Defect
VI. Casting without defects
Fig.5 casting without defects
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 5
VII. Testing Result
VIII. Casting Simulation for Connect Hinge by use of Auto-cast
Fig.6 Model of connect hinge Fig.7 Modified design
IX. Casting Simulation for Connect Hinge
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 6
Fig.8 Feeding cooling at top section of thick part
Fig.9 Feeding cooling at a lower section
Fig.10 Feeding Cooling does not show any hot spots
X. Comparison between the Traditional and Software method of gating system design
Mithari Ranjeet, Shinge Mahesh, Rajigare Pravin, International Journal of Advance Research, Ideas and
Innovations in Technology.
© 2016, IJARIIT All Rights Reserved Page | 7
Sr. No Point Traditional Method Software Method
1. Time Required to
design
This method required 15 to 18 days for
completed gating system design with
required output product.
This method required very less time than
the Traditional Method. It required only
maximum 4 to 5 days.
2. Percentage of
yield
By the Traditional Method we get the
70% yield.
By the Software Method we get the 70%
yield.
3. Cost of product In this cost of product increase. In this cost of product decrease.
4. Result of product In this method we get the result after
casting done.
In this method we get the result before
casting done.
5. Rejections In this we have rejected 8 products.
No rejections because we can check the
directly hot spot in software. So no any
defects in casting.
Conclusion
Gating system plays extremely important role in metal filling of mould. The design and development of this system is
therefore part and partial of the good quality of the casting. Every time rules may not lead to good quality of the casting
and also can in uneconomic production of casting resulting in to, Lower yield, Higher casting rejection at various stages
which mainly includes Hot spots , In gate shrinkage , Porosity ,Sand wash. To avoid such defects it is very much
essential that every foundry should have well defined and documented system for design development of gating system.
Chock area should be designed by calculation method not by thumb rule which will avoid turbulence and streamlined
metal supply to mould will come into existence, it also helps to avoid slag entry in the mold. Use of casting simulation
was found to help optimize the gating system dimensions leading to better yield. Further, from simulation it could be
revealed that the use of exothermic sleeves could help eliminating the hot spots and hence shrinkage defect.
References
[1] Mohamad Riyaz S H, Prasad Raikar “Yield improvement of cats part using computer aided casting simulation “ ,
IJARIIT, volume no 02, 2015, Page 858-862.
[2] N. Jaykumar, “Design and analysis of gating system for pump casing”, International journal of Engineering and
Technology, vol No. 5, Oct 2014, Page 2421-2425.
[3] Rabindra Behera, Kayal S, Sutradhar, G, “Solidification behaviour and detection of hotspots in aluminium alloy
casting, computer aided analysis and experimental validation”, International journal of Applied Engineering
Research, volume 1, No 4, pp. 715-726.
[4] S. Sulaiman , T.C. Keen, “Flow analysis along the runner and gating system of a casting process” Journal of Material
Processing Technology.1997.63 pp 690-695.
[5] Manufacturing Technology by P N Rao, volume 1, 4e, 2013.
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